The present invention relates to a system for guiding a missile in a direction of sight, comprising, at emission, a source of emission producing a light beam of which the axis defines the direction of sight and a device for modulating the emitted beam and, on the missile, at least one photo-detector and a processing circuit for determining, from the output signal from the detector, at least one coordinate of the missile with respect to the direction of sight, said coordinate being applied to the control surfaces of the missile to control the path of the missile on the direction of sight.
In known systems of this type, a rotating sight of relatively complicated form is generally used for modulating the beam, and the modulated beam thus produced is subject to diffraction.
It is an object of the invention to provide a guide system in which the modulation device functions according to an entirely different principle and is of very simple design.